Logical Key Hierarchy Research Articles

A survey on optimization-based approaches to Dynamic Centralized Group Key management

Abstract—In secure multicast communication, only authorized group members are able to receive the transmitted data. Key generation, distribution, and management are all carried out by a single entity (called the Key Server) in the centralized system. The main challenges of a dynamic centralized group key management scheme include scalability overhead, rekeying overhead, storage overhead, maintaining forward and backward secrecy, etc. Logical Key Hierarchy (LKH), one of the key management methods, uses a tree structure to manage keys to share with participants. Due to the fact that members may join or exit the group at any time during communication, a crucial problem in centralized group key management (CGKM) is minimizing rekeying costs while maintaining a balanced tree. The majority of CGKM methods effectively update the group key by modifying cryptographic techniques or based on logical/heuristic arguments. One of the efficient approaches is based on an optimization model with the two mentioned important objectives. In this paper, we conduct a survey on optimization-based approaches to dynamic CGKM, which can be divided into two categories based on logical/heuristic arguments and a rigorous mathematical optimization model.

Integrated IoT-Based Secure and Efficient Key Management Framework Using Hashgraphs for Autonomous Vehicles to Ensure Road Safety.

Autonomous vehicles offer various advantages to both vehicle owners and automobile companies. However, despite the advantages, there are various risks associated with these vehicles. These vehicles interact with each other by forming a vehicular network, also known as VANET, in a centralized manner. This centralized network is vulnerable to cyber-attacks which can cause data loss, resulting in road accidents. Thus, to prevent the vehicular network from being attacked and to prevent the privacy of the data, key management is used. However, key management alone over a centralized network is not effective in ensuring data integrity in a vehicular network. To resolve this issue, various studies have introduced a blockchain-based approach and enabled key management over a decentralized network. This technique is also found effective in ensuring the privacy of all the stakeholders involved in a vehicular network. Furthermore, a blockchain-based key management system can also help in storing a large amount of data over a distributed network, which can encourage a faster exchange of information between vehicles in a network. However, there are certain limitations of blockchain technology that may affect the efficient working of autonomous vehicles. Most of the existing blockchain-based systems are implemented over Ethereum or Bitcoin. The transaction-processing capability of these blockchains is in the range of 5 to 20 transactions per second, whereas hashgraphs are capable of processing thousands of transactions per second as the data are processed exponentially. Furthermore, a hashgraph prevents the user from altering the order of the transactions being processed, and they do not need high computational powers to operate, which may help in reducing the overall cost of the system. Due to the advantages offered by a hashgraph, an advanced key management framework based on a hashgraph for secure communication between the vehicles is suggested in this paper. The framework is developed using the concept of Leaving of Vehicles based on a Logical Key Hierarchy (LKH) and Batch Rekeying. The system is tested and compared with other closely related systems on the basis of the transaction compilation time and change in traffic rates.

Cluster space key management scheme based on threshold secret sharing and bilinear pairing

SummarySpace key management schemes play a critical role in space information network security services. However, the existing space key management schemes are inefficient. To overcome these problems, this paper proposed a cluster group key management scheme, in which the space nodes are divided into different clusters. The ground control center (GCC) is used as a private key generation center. The threshold technique based on low‐density parity‐check code (LDPC) is used in the group key management of the cluster‐heads. The key escrow is transferred to GCC, which is a compromise of efficiency and security. The logical key hierarchy is used to manage the group key of the cluster. Furthermore, the bilinear paring‐based cryptosystem is employed to provide the identification. The formalized security proof of the protocol using the Extended Canetti–Krawczyk (ECK) model is introduced to prove the authentication and security. The consistency, forward secrecy, backward secrecy, ability to against the collusion attack and performance are analyzed and simulated. The result shows that the proposed scheme takes lower storage cost and computational cost.

A Hierarchical Multicast Key Distribution Protocol

In secure group communication, group keys (GK) are used to ensure the confidentiality of communication. The group key distribution (GKD) is responsible for updating and distributing new group keys when the group membership changes. Most well-known GKD protocols are based on a logical key hierarchy (LKH), where only one group controller (GC) is used. These protocols have various issues, including a single point of failure, meaning that the GC often has a huge workload and can be easily overwhelmed. In this paper, we propose a hierarchical multicast key distribution protocol that supports multi-level controllers to manage a group. Each controller just needs to manage the next-level nodes, and if one fails, the superior controller can replace it with minimal work. The proposed protocol effectively balances the work of controllers, greatly improves the reliability of the group key distribution, and also allows group members to build dynamic conferences without controllers. We provide a security proof of the proposed protocol in a symbolic security model and compare it to other protocols in terms of efficiency, functionality, and security.

Analysis of Tree Structure for Secure Group Communication Using LKH Approach

In secure Group communication for applications such as pay per view, teleconferencing, and video conferencing, key management method with logarithmic computation, storage time and bandwidth efficiency are expected. Major aspects with key management are initializing the group with a group key and rekeying the group. The server maintains a key tree. Rekeying is mandatory due to dynamic group nature (join/leave operations) or periodic rekeying. Logical Key Hierarchy has a logarithmic rekeying cost if the key tree is balanced, over multiple rekeying operations key tree is not balanced and LKH yields worst Rekeying cost. To achieve logarithmic cost either keep the key tree balanced or restructure the key tree in such a way that it will still result in the best rekeying cost. This paper explores tree structures using the Logical Key Hierarchy (LKH) approach to find an optimal tree structure for an application.

RETRACTED ARTICLE: Efficient data sensing with group key management for intelligent automation system by one-way key derivation in wireless networks

Over the last century, Wireless Sensor Network (WSN) has given major advances in several distinguishable fields. In addition, it has also evolved many features such as high device heterogeneity, high scale and supporting multiple applications. In WSN, Key management is employed (involves) as a significant component of network security, especially in multi-cast based applications and services. Group key management has a vital role in multi-cast secure communication with huge number of group members. Group key must always be updated dynamically to all groups in the network and keys to be redistributed currently to active members only. Consequently, a secret key called session key for a group of members is stored in key trees that are shared efficiently between them, in order to achieve secure group communication. The key trees are used to encrypt with other keys and data are transmitted to ensure security. Logical key hierarchy (LKH) is a hierarchical structure of multiple keys to provide a scalable and secrecy for group communication. This research work proposes a new hierarchical group key management (HGKM) using multiple logical key trees for dynamic groups in order to enhance the Quality of Service of the network. Among the multiple logical trees, primary tree can be selected by tree selection algorithm. In WSN, there are high numbers of members joining or leaving the group at any time, resulting with rekeying process becoming too large. This leads to degraded efficiency of tree-based key management system. Further, communication overhead of rekeying process can be mitigated by one-way key derivation method which integrates with multiple logical key trees. In this method, tree server does not need to be encrypted. Rather, it involves in sending a new key to members who are capable of derive their own keys in same way the server does. This results with a need for less number of encrypted keys for each rekeying process within the group tree. The fixed interval time is called batch time, which is applied in each rekeying process after nodes join or leave the group. The proposed approach can improve the bandwidth utilization effectively. The proposed HGKM method is implemented in Network Simulator (NS-2) environment and obtained results are compared with existing two methods such as LKH and multiple logical tree key management (MLT-KM). QOS of proposed approach is evaluated in terms of Bandwidth Efficiency.

A Logical Key Hierarchy Based Approach to Preserve Content Privacy in Decentralized Online Social Networks

Distributed Online Social Networks (DOSNs) have been proposed to shift the control over user data from a unique entity, the online social network provider, to the users of the DOSN themselves. In this paper we focus on the problem of preserving the privacy of the contents shared to large groups of users. In general, content privacy is enforced by encrypting the content, having only authorized parties being able to decrypt it. When efficiency has to be taken into account, new solutions have to be devised that: i) minimize the re-encryption of the contents published in a group when the composition of the group changes; and, ii) enable a fast distribution of the cryptographic keys to all the members ( $n$ n ) of a group, each time a set of users is removed from or added to the group by the group owner. Current solutions fall short in meeting the above criteria, while our approach requires only $O(d\cdot log_d (n))$ O ( d · l o g d ( n ) ) encryption operations when a user is removed from a group (where $d$ d is an input parameter of the system), and $O(2\cdot log_d (n))$ O ( 2 · l o g d ( n ) ) when a user joins the group. The effectiveness of our approach is evaluated through simulations based on a real online social network.

A Group Key Management Scheme for WSN Based on Lagrange Interpolation Polynomial Characteristic

According to the main group key management schemes logical key hierarchy (LKH), exclusion basis systems (EBS) and other group key schemes are limited in network structure, collusion attack, high energy consumption, and the single point of failure, this paper presents a group key management scheme for wireless sensor networks based on Lagrange interpolation polynomial characteristic (AGKMS). That Chinese remainder theorem is turned into a Lagrange interpolation polynomial based on the function property of Chinese remainder theorem firstly. And then the base station (BS) generates a Lagrange interpolation polynomial function f(x) and turns it to be a mix-function f(x)’ based on the key information m(i) of node i. In the end, node i can obtain the group key K by receiving the message f(m(i))’ from the cluster head node j. The analysis results of safety performance show that AGKMS has good network security, key independence, anti-capture, low storage cost, low computation cost, and good scalability.

A Computation-Efficient Group Key Distribution Protocol Based on a New Secret Sharing Scheme

With the development of 5G and the Internet of Things (IoT), mobile terminals are widely used in various applications under multicast scenarios. However, due to the limited computation resources of mobile terminals, reducing the computation cost of members in group key distribution processes of dynamic groups has become an important issue. In this paper, we propose a computation-efficient group key distribution (CEGKD) protocol. First, an improved secret sharing scheme is proposed to construct faster encryption and decryption algorithms. Second, the tree structure of logical key hierarchy (LKH) is employed to implement a simple and effective key-numbering method. Theoretical analysis is given to prove that the proposed protocol meets forward security and backward security. In addition, the experiment results show that the computation cost of CEGKD on the member side is reduced by more than 85% compared with that of the LKH scheme.

Hierarchical group key management for secure data sharing in a cloud‐based environment

SummaryIn cloud environment, the importance of security for the outsourced data has increased much, since the data is maintained and controlled by the semi‐trusted third‐party cloud providers. Data Security is one of the major factors to be considered in group data sharing. Using the secret key, the entire file is encrypted directly in a conventional security framework; however, in a cloud‐based environment for group mechanism, this framework cannot be applied as there is a problem of key distribution. This research paper proposes an efficient hierarchical‐based group key mechanism for a cloud‐based environment. This proposed system relies on Key Distribution Server (KDS), which performs cryptographic key operations for securing the data in the cloud. Also, this system uses logical key hierarchy (LKH) protocol to maintain hierarchical tree for scalability. The group key is generated using the group member secret values and a secret value assigned by the KDS server. Performance analysis of this system shows that the proposed key management system is more efficient and much suitable for cloud environment.

An efficient protocol for secure multicast key distribution in the presence of adaptive adversaries

In this paper, an efficient construction of multicast key distribution schemes based on semantically secure symmetric-key encryption schemes and cryptographically strong pseudo-random number generators is presented and analyzed. The proposed scheme is provably secure against adaptive adversaries leveraging the security amplification technique defined over the logical key hierarchy structures. Our protocol tolerates any coalition of revoked users; in particular, we do not assume any limit on the size or structure of the coalition. The proposed scheme is efficient as a performance of Join or Leave procedure requires $2 \log(N)$ multicast activities defined over a sibling ancestor node set, $2 \log(N)$ internal state updates of the underlying pseudo-random number generator and $2\log(N)$ symmetric-key encryption activities for $N$ users in a session.

A key management architecture and protocols for secure smart grid communications

Providing encrypted communications among power grid components is expected to be a basic requirement of smart grid systems in the future. Here, we propose a key management architecture and associated protocols tailored to support encrypted smart grid communications. The architecture consists of two levels structured around the grid control system hierarchy. At the top level, which consist of control centers and regional coordinators, a bottom-up key structure is adopted using hash chaining and a logical key hierarchy. The lower level of the architecture consists of the regional coordinators i.e., substations and distribution systems and remote ends e.g., meters and pole-top sensors and utilizes a top-down key management approach built on an inverse element method. The proposed key management schema supports the hierarchical structure of the smart grid control mechanisms, and it takes the resource and electronic/physical security differences of the control levels into account. We define a set of protocols utilizing the architecture to provide secure unicast, multicast, and broadcast communications. Furthermore, we illustrate how the architecture is flexible enough to easily handle power grid nodes joining and leaving the system at the different levels. Lastly, we compare the proposed schema with existing ones and show that our architecture can achieve efficient key management to provide secure communications. Copyright © 2016 John Wiley & Sons, Ltd.

TALK: Topology Aware LKH Key Management

Cryptographic key management for wireless sensor networks (WSNs) and mobile ad-hoc networks (MANETs) is a particularly challenging task, as they mostly consist of high counts of resource constrained nodes, especially when group communication and dynamic network membership capabilities are required. The logical key hierarchy (LKH) is a well-known class of protocols which aims to solve the key management problem and minimize rekeying overhead, using hierarchical structures and taking advantage of multicast communication. In this work we propose a method for obtaining LKH structures by taking into account the topology of the underlying network, leading to a further decrease in rekeying costs, in terms of packet transmissions.

An Efficient Key Management Protocol for Multi-Microgrid Distribution System

This paper studies network security of the multi-microgrid distribution system (MMDS) composing of a large number of distributed power-islands. First, a hierarchical communication model for MMDS is designed . Then we analyze the security vulnerabilities. Finally, proposes an efficient secure key management protocol by combining Iolus framework and logical key hierarchy (LKH).

Performance and Rekeying Analysis of Multicast Security in LTE

Multimedia Broadcast Multicast Services (MBMS) is apoint-to-multipoint interface specification for existing and upcoming3GPP cellular networks, which is designed to provide efficient delivery ofbroadcast and multicast services, within a cell or within the core network. Target applications includemobile TV and radio broadcasting, file delivery and emergency ale rts.The main goal of this paper is to assess the performance of the Secure Multicast Overlay (SMO) and the Group Security Association (GSA). We functionally compare GSA with SMO, in terms of Keys management procedures and look up policies showing that GSA solution is appropriate in certain circumstances and SMO solution is appropriate in others. The comparison will be for different parameters and different services.Also the computational cost and storage cost for Logical Key Hierarchy (LKH) tree with and without dynamic rekeying will be calculated.

Key Management in Secure Satellite Multicast Using Key Hypergraphs

Satellite networks play an important role in today's information age because they can provide the global coverage services. Information security is an important concern in satellite multicast communications, where eavesdropping can be performed much easier than the fixed terrestrial networks. In this work, a novel multicast key management scheme based on key hypergraph for satellite networks on a predefined communication scenario is proposed. We use logical key hierarchy and distributed-logical key hierarchy as reference models for performance comparisons. It is shown that the proposed multicast key management scheme is scalable to large dynamic groups and minimizes satellite bandwidth usage.

An Efficient Group Key Management Using Code for Key Calculation for Simultaneous Join/Leave: CKCS

This paper presents an efficient group key management protocol, CKCS (Code for Key Calculation in Simultaneous join/leave) for simultaneous join/leave in secure multicast. This protocol is based on logical key hierarchy. In this protocol, when new members join the group simultaneously, server sends only the group key for those new members. Then, current members and new members calculate the necessary keys by node codes and one-way hash function. A node code is a random number which is assigned to each key to help users calculate the necessary keys. Again, at leave, the server just sends the new group key to remaining members. The results show that CKCS reduces computational and communication overhead, and also message size in simultaneous join/leave.

Key Establishment Scheme for Distribution Automation System Using Logical Key Hierarchy Approach

Ethernet Passive Optical Networks (EPONs) are promising communication technologies for distribution automation system (DAS). However, EPONs have very specific security requirements, due to the broadcast character of the transmission medium. Based on the identity-based cryptography (IBC), and utilizing logical key hierarchy (LKH) approach, this paper presents an efficient key establishment scheme for distribution automation system using EPON. And the analysis results are also given in the paper.

RiSeG: a ring based secure group communication protocol for resource-constrained wireless sensor networks

Securing group communication in wireless sensor networks has recently been extensively investigated. Many works have addressed this issue, and they have considered the grouping concept differently. In this paper, we consider a group as being a set of nodes sensing the same data type, and we alternatively propose an efficient secure group communication scheme guaranteeing secure group management and secure group key distribution. The proposed scheme (RiSeG) is based on a logical ring architecture, which permits to alleviate the group controller's task in updating the group key. The proposed scheme also provides backward and forward secrecy, addresses the node compromise attack, and gives a solution to detect and eliminate the compromised nodes. The security analysis and performance evaluation show that the proposed scheme is secure, highly efficient, and lightweight. A comparison with the logical key hierarchy is preformed to prove the rekeying process efficiency of RiSeG. Finally, we present the implementation details of RiSeG on top of TelosB sensor nodes to demonstrate its feasibility.

Challenges and trends in wireless ubiquitous computing systems

In the last decade, the Internet paradigm has been evolving toward a new frontier with the emergence of ubiquitous and pervasive systems, including wireless sensor networks, ad hoc networks, RFID systems, and wireless embedded systems. In fact, while the initial purpose of the Internet was to interconnect computers to share digital data at large scale, the current tendency is to enable ubiquitous and pervasive computing to control everything anytime and at a large scale. This new paradigm has given rise to a new generation of networked systems, commonly known as Internet-of-Things or Cyber-Physical Systems. The research community has actively investigated the underlying challenges pertaining to these systems, as they fundamentally differ from the classical problems due to their inherent constraints. This special issue presents six papers covering various topics in personal and ubiquitous computing. The first paper entitled ‘‘RiSeG: A Ring Based Secure Group Communication Protocol for Wireless Sensor Networks’’ deals with security in ubiquitous systems. The paper presents a new approach for secure group management in wireless sensor networks. The proposed approach is based on a logical ring architecture, which permits to alleviate the group controller’s task in updating the group key. The proposed scheme also provides backward and forward secrecy, addresses the node compromise attack, and gives a solution to detect and eliminate the compromised nodes. The authors evaluated their scheme in terms of storage, computation, and communication costs and compared its behavior against the Logical Key Hierarchy (LKH) scheme. It has been shown that RiSeG requires less storage cost and reduces computation and communication costs at the Group Controller as compared with LKH. The paper goes beyond theoretical work and proposes a realworld implementation, which first proved that RiSeG is applicable to WSNs and also showed that the performance results in terms of execution time, energy consumption, and memory consumption are satisfactory. The second paper entitled ‘‘Stability routing with constrained path length for improved routability in dynamic MANETs’’ addresses the problem of enhancing the routing validity in mobile wireless multi hop ad hoc networks. In proactive routing, routes are established and updated periodically and consequently loose their pertinence as time tics away from the start of their updating instants. Authors argue that routability, defined as the validity of established routes, stands among the most centric metric impacting the network efficiency. Indeed, in dynamic networks, traffic routed through invalid routes not only amounts to a waste of valuable resources but will never be delivered to its destination. In the quest of improving routability in dynamic networks, the authors considered a two-constrained QoS routing problem with one superlative constraint and one comparative constraint. In its general form, this is an NP hard problem. The authors proposed a novel exact algorithm and then instantiated the problem to solve the optimal integer weight-constrained path length A. Belghith (&) University of Manouba, Manouba, Tunisia e-mail: abdelfattah.belghith@ensi.rnu.tn